Increased Transcription of Occludin and MUC2 in Subjects with Metabolic Syndrome Following Modulation of the Gut Microbiota by a Diet Rich in Arabinoxylan and Resistant Starch

Background:A dysbiotic gut microbiota and a weakened colonic defense barrier might contribute to the low-grade inflammation associated with the metabolic syndrome (MetS). Animal studies indicate that consumption of dietary fibers change the gut microbiota, enhance the colonic defense barrier, and reduce inflammation.

We hypothesized that a diet rich in the two dietary fibers, arabinoxylan and resistant starch, would strengthen the colonic defense barrier evaluated by increased occludin and MUC2 transcription and decreased fecal calprotectin, a marker of gut neutrophil infiltration.

Methods:Nineteen subjects with MetS completed a randomized crossover study with two 4-week diet interventions encompassing a healthy-carbohydrate diet (HCD) rich in arabinoxylan and resistant starch and a low-fiber western style diet. Before and after each intervention we performed endoscopy with biopsies and collected stool samples.

Results: The healthy-carbohydrate diet changed the gut microbiome and most distinctly enhanced Bifidobacterium (p<0.01). Colonic transcription of occludin increased by 17% (p=0.03) and MUC2 by 21% (p=0.02) after HCD, whereas fecal calprotectin decreased by 30% (p<0.05).

Conclusion: Consumption of a diet rich in arabinoxylan and resistant starch for four weeks modified the gut microbiome, increased colonic occludin and MUC2 transcription and decreased fecal calprotectin suggesting a reinforced colonic defense barrier in subjects with MetS.